Condensible gas botanical extraction systems and methods

ABSTRACT

An apparatus for the extraction of compounds from botanical material using a condensable gas solvent includes sequential extraction and separation stages.

FIELD

This disclosure relates generally to apparatus and methods for theextraction of compounds from botanical material using a condensable gassolvent. More specifically, this disclosure relates to apparatus andmethods for the extraction of compounds from cannabis, such as aliphaticaldehydes, monoterpenes, and cannabinoids.

INTRODUCTION

The following is not an admission that anything discussed below is partof the prior art or part of the common general knowledge of a personskilled in the art.

Botanicals extracts are a growing product class in the cannabisindustry. Advantageously, extracts may have some or all of the benefitsof the original plant, in a convenient concentrated form.

Popular methods used to extract various compounds from botanicalsinvolve the use of solvents, typically alcohol or water (often in theform of steam). These solvents diffuse the plant material and draw outone or more plant compounds. More often than not, the solvent is removedfrom the final extract. In order to extract the more hydrophobiccompounds, hydrocarbon or chlorinated solvents may be used, subsequentlyleaving residues that may be challenging to remove or minimize.

SUMMARY

The following introduction is provided to introduce the reader to themore detailed discussion to follow. The introduction is not intended tolimit or define any claimed or as yet unclaimed invention. One or moreinventions may reside in any combination or sub-combination of theelements or process steps disclosed in any part of this documentincluding its claims and figures.

Condensable gas solvent may be used to extract one or more compoundsfrom botanical material, such as a cannabis feedstock. Advantageously,condensable gases can be liquefied at moderate pressures at ambienttemperature. Condensable gas solvents may also for be used forextraction at relatively wide temperature and pressure range. This mayenable improved solubility performance, and/or provide a more completeextraction in less time when compared to other solvents.

In particular, carbon dioxide (CO₂) is considered to be a preferredsolvent for cannabis extraction. For example, it is regarded asnon-toxic, environmentally friendly, relatively inexpensive, and leavesno residue when the extracted compounds are separated from the solvent.Also, the low viscosity of supercritical carbon dioxide may allow it topenetrate into botanical material more easily, while its diffusivity mayallow for faster extractions.

In accordance with one aspect of this disclosure, which may be usedalone or in combination with one or more other aspects, apparatus forthe extraction of compounds from botanical material using a condensablegas solvent includes using a sonic flow nozzle that is positionedadjacent a cyclone chamber to introduce a mixture of a solvent and abotanical extract into a cyclone chamber. The sonic flow nozzle may beproximate (e.g., immediately upstream of) a tangential fluid inlet ofthe cyclone chamber or a tangential inlet may comprise or consist of asonic flow nozzle.

According to this aspect, the feed to a cyclone separator (e.g., acompressible gas solvent (e.g. CO₂) and a botanical extract dissolvedtherein) may be accelerated to sonic or supersonic speeds and introduceddirectly into the cyclone chamber. Accordingly, a solvent containingextracted botanical elements may exit the sonic flow nozzle at asupersonic velocity and be directly tangentially introduced into acyclone separator. An advantage of this design is that it may promotegreater separation efficiency, in that most, substantially all, oressentially all of the extracted material dissolved or contained in thesolvent stream may be separated from the gas solvent. For example, morethan 85%, 90%, 95%, 96%, 97%, 98%, or 99% of the extracted materialdissolved in the solvent stream may be separated from the gas solvent asan unfoamed extract as exemplified in FIG. 9. As a result, gaseoussolvent exiting the cyclonic separator may have little or no solute. Forexample, less than 15%, 10%, 5%, 4%, 3%, 2%, or 1% of extractedbotanical compound(s) may remain in the gaseous solvent exiting thecyclonic separator. A further advantage is that this may allow ‘clean’(i.e. substantially or completely extract-free) solvent to be recycledto an extraction chamber.

This separation efficiency may be contrasted with typical cycloneseparator systems which use a typical cyclone inlet wherein there may besignificant volumes of solvent in the botanical extract exiting acyclone separator.

For example, the botanical extract exiting a cyclone separator may be inthe form of an emulsion or foamed liquid extract which may contain 2% ormore solvent (see for example FIG. 8). The downstream processing of suchproducts is difficult as the extract is not easily flowable and may foulthe low pressure piping and compression pumps downstream of theseparator.

In contrast, in accordance with this aspect, the solvent-extract streamfrom the extraction chamber may undergo simultaneous depressurizationand acceleration immediately upstream of, or as it enters the cyclonechamber, forming liquid droplets of extracted compounds which may flowunder the influence of gravity down the wall of a cyclone separator soas to be collected as, e.g., an unfoamed liquid (see for example FIG.9).

A further advantage of this aspect is that it may allow the sonic flownozzle to be operated in a ‘choked’ state. An advantage of operating theflow nozzle under ‘choked’ conditions is that pressure disturbancesupstream of the sonic flow nozzle may be inhibited or prevented frommoving downstream into the cyclonic separator, and thus may be inhibitedor prevented from causing undesirable pulsations and/or vortex flowinstabilities during the decompression and/or separation that occurs inthe cyclonic separator.

In accordance with this aspect, there is provided an apparatus for theextraction of compounds from botanical material using a condensable gassolvent, the apparatus comprising:

(a) an extraction chamber having a solvent outlet;

(b) a cyclonic separator comprising a cyclone chamber having a cyclonictangential fluid inlet and a fluid outlet;

(c) a solvent flow path extending from the solvent outlet of theextraction chamber to the cyclonic tangential fluid inlet; and,

(d) a sonic flow nozzle positioned in the solvent flow path adjacent thecyclonic tangential fluid inlet.

In any embodiment, the sonic flow nozzle may be positioned at anupstream end of the cyclonic tangential fluid inlet whereby the solventpassing through the sonic flow nozzle enters the cyclone chamber atsonic velocity.

In any embodiment, the sonic flow nozzle may comprise the cyclonictangential fluid inlet.

In any embodiment, the extraction chamber may be operated below 0° C.and with the solvent in a liquid or a supercritical phase, and thesolvent flow path may further comprise a heater proximate an inlet ofthe sonic flow nozzle wherein the solvent exiting the heater is gaseous.

In any embodiment, the apparatus may further comprise a solvent returnpath extending from the fluid outlet of the cyclonic separator to theextraction chamber.

In any embodiment, the outlet of the sonic flow nozzle may be positionedat an inlet port of the cyclone separator.

In accordance with this aspect, there is also provided a method forextracting compounds from botanical material using a condensable gassolvent, the method comprising:

(a) in an extraction chamber, using the condensable gas solvent toextract at least one compound from a feedstock of botanical material;

(b) withdrawing a liquid solvent containing the at least one compoundextracted from the feedstock from the extraction chamber and conveyingthe liquid solvent through a solvent flow path to a sonic flow nozzleand obtaining solvent at a supersonic velocity; and,

(c) directly tangentially introducing the solvent exiting the sonic flownozzle at a supersonic velocity into a cyclone separator.

In any embodiment, the solvent in the flow path may be in a phasecomprising at least one of a supercritical phase and a liquid phase.

In any embodiment, the solvent in the extraction chamber may be in aliquid phase and the solvent in the flow path may be in a supercriticalphase.

In any embodiment, the method may further comprise heating the solventto a gaseous phase prior to the solvent entering the sonic flow nozzle.

In any embodiment, the solvent in the extraction chamber may be in aliquid phase and the solvent in the flow path may be in a supercriticalphase.

In any embodiment, the method may further comprise separating at least aportion of the at least one compound from the solvent in the cycloneseparator and collecting the at least one compound as an unfoamedliquid.

In any embodiment, the method may further comprise heating the cycloneseparator whereby the at least one compound that is separated in thecyclone separator may be heated and its viscosity may be reduced.

In any embodiment, the outlet of the sonic flow nozzle may be positionedadjacent the cyclone separator and the method may further comprisedirecting solvent exiting the sonic flow nozzle to avoid the solventcontacting an inlet port of the cyclone separator.

In any embodiment, the outlet of the sonic flow nozzle may be positionedat an inlet port of the cyclone separator and the method may furthercomprise conveying solvent exiting the sonic flow nozzle immediatelyinto the cyclone separator.

In any embodiment, the feedstock of botanical material may comprisecannabis and the method may further comprise obtaining as the at leastone compound extracted from the feedstock at least one of an aliphaticaldehyde, a terpene, and a cannabinoid.

In accordance with another aspect of this disclosure, which may be usedalone or in combination with one or more other aspects, a method forextracting compounds from botanical material comprising cannabis using acondensable gas solvent includes extracting a compound from the cannabisusing condensable gas solvent in a liquid and/or supercritical phase. Aliquid stream of solvent and the extracted compound is conveyed to acyclone chamber, and solvent in the liquid stream is converted to agaseous phase upstream of the cyclone chamber. Solvent in the gaseousphase is then directed into the cyclone chamber at sonic velocity.

An advantage of this aspect is that solvent containing extractedcompounds may be maintained in a liquid and/or supercritical phaseupstream of the cyclone chamber, which may facilitate maintaining thesolvent density at a level sufficient to inhibit or prevent theextracted compounds from being disassociated from the solvent upstreamof the cyclone chamber thereby preventing or reducing fouling of theflow path from the extractor to the cyclone separator.

In accordance with this aspect, there is provided a method forextracting compounds from botanical material comprising cannabis using acondensable gas solvent, the method comprising:

(a) in an extraction chamber, using the condensable gas solvent in aphase comprising at least one of a supercritical phase and a liquidphase to extract at least one compound from the cannabis;

(b) withdrawing a liquid stream comprising the solvent the at least onecompound and conveying the liquid stream along a solvent flow pathextending from the extraction chamber to a cyclone chamber having afluid inlet;

(c) converting the solvent in the liquid stream to a gaseous phaseupstream of the cyclone chamber; and,

(d) directing the solvent in the gaseous phase into the cyclone chambervia the fluid inlet at sonic velocity.

In any embodiment, conveying the liquid stream containing the at leastone compound may comprise directing solvent through a sonic flow nozzlepositioned in the solvent flow path upstream of the fluid inlet.

In any embodiment, the fluid inlet may comprise the sonic flow nozzle.

In any embodiment, the fluid inlet may be a tangential air inlet.

In any embodiment, the method may further comprise separating at least aportion of the at least one compound from the solvent in the cyclonechamber and collecting the at least one compound as an unfoamed liquid.

In any embodiment, the method may further comprise heating the cyclonechamber whereby the at least one compound that is separated in thecyclone chamber may be heated and its viscosity may be reduced.

In any embodiment, the method may further comprise selecting thecondensable gas solvent from at least one of carbon dioxide, ahydrocarbon, preferably a haloalkane, Xenon, nitrous oxide, and sulfurhexafluoride.

In any embodiment, the method may further comprise selecting carbondioxide as the condensable gas solvent.

In any embodiment, the at least one compound extracted from thefeedstock may comprise at least one of an aliphatic aldehyde, a ketone,an ester, a terpene, and a cannabinoid.

In accordance with another aspect of this disclosure, which may be usedalone or in combination with one or more other aspects, a method forextracting compounds from botanical material comprising cannabis using acondensable gas solvent includes providing a frozen feedstock ofbotanical material (e.g. all or substantially all of the water in thefeedstock is in a solid phase) to an extraction chamber, and extractinga compound from the feedstock using a condensable gas solvent whilemaintaining the feedstock in a frozen state.

An advantage of extracting compounds from frozen botanical material isthat it may impede or prevent water in the botanical material from beingdissolved by the solvent. This may result in a more ‘complete’ extractbeing obtained, and may also improve the speed and/or efficiency of thesolvent extraction. For example, some terpenes are somewhat watersoluble. If the recovered extract contains a significant amount ofwater, then when the water is removed, some of the terpenes may be lost.

Another possible advantage is that this may reduce or obviate the needto desiccate the material prior to extraction. This may be particularlyadvantageous for extracting compounds from a cannabis feedstock. Forexample, one or more compounds typically present in cannabis may belost, damaged, or otherwise adversely affected during a typical dryingprocess.

In accordance with this broad aspect, there is provided a method forextracting compounds from botanical material comprising cannabis using acondensable gas solvent, the method comprising:

(a) providing a feedstock of the botanical material to an extractionchamber wherein water in the feedstock is in a solid phase;

(b) extracting at least one compound from the feedstock of the botanicalmaterial using the condensable gas solvent while maintaining thefeedstock in a frozen state and obtaining solvent containing the atleast one extracted compound;

(c) withdrawing a solvent stream containing the at least one extractedcompound from the extraction chamber; and,

(d) separating the at least one extracted compound from the solventstream.

In any embodiment, the feedstock of botanical material provided in theextraction chamber may have a moisture content of at least 9%.

In any embodiment, the feedstock of botanical material provided in theextraction chamber may have a moisture content of at least 12%.

In any embodiment, in step (a) at least 50% of the water in thefeedstock may be in the solid phase.

In any embodiment, the method may further comprise controlling processconditions of the extraction chamber such that the solvent in theextraction chamber is in at least one of a liquid phase and asupercritical phase.

In any embodiment, step (d) may comprise separating the at least oneextracted compound from the solvent stream in a cyclonic separator.

In any embodiment, in step (a), the feedstock may be introduced into theextraction chamber in an unfrozen state.

In any embodiment, the feedstock of botanical material introduced to theextraction chamber may have a moisture content of at least 5%.

In any embodiment, the solvent in the extraction chamber may be in aliquid phase.

In any embodiment, the method may further comprise obtaining freshfeedstock and step (a) may comprise introducing the fresh feedstock intothe extraction chamber.

In any embodiment, the method may further comprise introducing the freshfeedstock having a moisture content of at least 5% into the extractionchamber.

In any embodiment, the solvent in the extraction chamber may be in aliquid phase.

In any embodiment, the at least one compound extracted from thefeedstock may comprise at least one of an aliphatic aldehyde, a terpene,and a cannabinoid.

In accordance with another aspect of this disclosure, which may be usedalone or in combination with one or more other aspects, a method forextracting compounds from botanical material using a condensable gassolvent includes extracting the botanical material at conditions atwhich a condensable solvent is in a liquid phase and heating the solventcontaining at least one compound extracted from the botanical materialin a heating zone located upstream from a cyclone separator. The heatingzone may be proximate to or immediately upstream of a cyclone separator.Accordingly, the solvent is heated and conveyed to a cyclone chamber(e.g., a tangential inlet of a cyclone separator, which may comprise orconsist of a sonic flow nozzle) at conditions at which the solvent is ina gaseous phase. Accordingly, the solvent may be conveyed to the cycloneinlet as a liquid and converted to a gas upstream or immediatelyupstream of a sonic flow nozzle or a tangential cyclone inlet.

An advantage of this design is that solvent containing extractedcompounds may be heated and brought to an inlet of a flow nozzle in agaseous phase, which may facilitate maintaining the solvent density at alevel sufficient to inhibit or prevent the extracted compounds frombeing disassociated from the solvent upstream of the flow nozzle,thereby preventing or reducing fouling of the flow path from theextractor to the cyclone separator.

In accordance with this broad aspect, there is provided a method forextracting compounds from botanical material using a condensable gassolvent, the method comprising:

(a) providing a feedstock of botanical material and condensable gassolvent in an extraction chamber at conditions at which the solvent isat least primarily in a liquid phase;

(b) conveying solvent containing at least one compound extracted fromthe feedstock along a solvent flow path extending from the extractionchamber to a heating zone;

(c) heating the solvent and conveying the solvent from the heating zoneto an inlet of a flow nozzle at conditions at which the solvent is atleast primarily in a gaseous phase; and,

(d) directing the gaseous solvent to a cyclone chamber and operating thecyclone chamber at conditions at which the solvent within the cyclonechamber is primarily in a gas phase and the at least one compoundextracted from the feedstock is primarily in a liquid phase.

In any embodiment, the flow nozzle may be a sonic flow nozzle and themethod may further comprise obtaining solvent exits the outlet of theflow nozzle at sonic velocity.

In any embodiment, controlling process conditions of the extractionchamber may comprise bringing the temperature of solvent in theextraction chamber to a temperature at or below the freezing point ofwater, such that at least a portion of water in the feedstock ofbotanical material is in a solid phase.

In accordance with another aspect of this disclosure, which may be usedalone or in combination with one or more other aspects, apparatus forthe extraction of compounds from botanical material is provided. Theapparatus includes an extraction chamber, and two or more cyclonicseparation stages for removing extracted compounds from a solventstream. At least one valve is operable to selectively direct solventfrom the extraction chamber to one of the cyclonic separation stages.

An advantage of this design is that the cyclonic separation stages mayeach be configured to preferentially separate certain compounds orclasses of compounds from a solvent stream. For example, a firstcyclonic separator may be configured or ‘tuned’ to preferentially removea first series of extracted compounds from a solvent stream, and asecond cyclonic separator may be configured or ‘tuned’ to preferentiallyremove a second, higher molecular weight, series of extracted compoundsfrom a solvent stream. This may allow a solvent stream containingcertain compound(s) to be directed from the extraction chamber to thecyclonic separator best suited to remove those compound(s).

In accordance with this broad aspect, there is provided apparatus forthe extraction of compounds from botanical material, the apparatuscomprising:

(a) an extraction chamber;

(b) a first cyclonic separation stage comprising at least one firststage cyclonic separator wherein the at least one first stage cyclonicseparator is configured to remove a first series of extracted compoundshaving a first average molecular weight from a solvent stream;

(c) a first solvent flow path extending from the extraction chamber tothe first cyclonic separation stage;

(d) a second cyclonic separation stage comprising at least one secondstage cyclonic separator wherein the at least one second stage cyclonicseparator is configured to remove a second series of extracted compoundsfrom a solvent stream wherein the second series of extracted compoundshas a second average molecular weight that is higher than the firstaverage molecular weight;

(e) a second solvent flow path extending from the extraction chamber tothe second cyclonic separation stage; and,

(f) at least one valve operable to selectively direct solvent exitingthe extraction chamber to one of the first cyclonic separation stage andthe second cyclonic separation stage.

In any embodiment, the apparatus may further comprise:

a third cyclonic separation stage comprising at least one third stagecyclonic separator wherein the at least one third cyclonic stageseparator is configured to remove a third series of extracted compoundsfrom a solvent stream wherein the third series of extracted compoundshas a third average molecular weight that is higher than the secondaverage molecular weight; and,

a third solvent flow path extending from the extraction chamber to thethird cyclonic separation stage,

wherein the at least one valve is operable to selectively direct solventexiting the extraction chamber to one of the first cyclonic separationstage, the second cyclonic separation stage, and the third cyclonicseparation stage.

In any embodiment, solvent obtained from the extraction chamber mayrotate at a first speed in the at least one first stage cyclonicseparator and solvent obtained from the extraction chamber may rotate ata second speed in the at least one second stage cyclonic separatorwherein the second speed may be different than the first speed.

In any embodiment, solvent obtained from the extraction chamber mayrotate at a first speed in the at least one first stage cyclonicseparator, solvent obtained from the extraction chamber may rotate at asecond speed in the at least one second stage cyclonic separator whereinthe second speed may be different than the first speed, and solventobtained from the extraction chamber may rotate at a third speed in theat least one third cyclonic separator wherein the third speed may bedifferent than the first speed and the second speed.

In any embodiment, the first solvent flow path may comprise a commonsolvent flow path portion downstream of the extraction chamber andupstream of the at least one valve and a first segregated solvent flowpath portion downstream of the at least one valve and upstream of thefirst cyclonic separation stage, and wherein the second solvent flowpath may comprise the common solvent flow path portion and a secondsegregated solvent flow path portion downstream of the at least onevalve and upstream of the second cyclonic separation stage.

In any embodiment, the first solvent flow path may comprise a commonsolvent flow path portion downstream of the extraction chamber andupstream of the at least one valve and a first segregated solvent flowpath portion downstream of the at least one valve and upstream of thefirst cyclonic separation stage, and wherein the second solvent flowpath may comprise the common solvent flow path portion and a secondsegregated solvent flow path portion downstream of the at least onevalve and upstream of the second cyclonic separation stage, and whereinthe third solvent flow path may comprise the common solvent flow pathportion and a third segregated solvent flow path portion downstream ofthe at least one valve and upstream of the third cyclonic separationstage.

In any embodiment, the apparatus may further comprise an extractioncontrol system for regulating at least one of a temperature and apressure of solvent in the extraction chamber, the extraction controlsystem may be configured to operate the extraction chamber under atleast a first set of process conditions and a second set of process ofconditions, and wherein, while the extraction chamber is being operatedunder the first set of process conditions, the at least one valve may beconfigured to direct solvent exiting the extraction chamber to the firstcyclonic separation stage, and wherein, while the extraction chamber isbeing operated under the second set of process conditions, the at leastone valve may be configured to direct solvent exiting the extractionchamber to the second cyclonic separation stage.

In accordance with another aspect of this disclosure, which may be usedalone or in combination with one or more other aspects, a method ofextracting compounds from botanical material is provided. First, solventis used under a first set of process conditions to preferentiallyextract a first compound from a feedstock of botanical material, andsolvent containing the first extracted compound is conveyed to a firstcyclonic separation stage. Next, solvent is used under a second set ofprocess conditions to preferentially extract a second compound from thefeedstock, and solvent containing the second extracted compound isconveyed to a second cyclonic separation stage.

An advantage of using condensable gas as a solvent is that it may allowthe preferential extraction (or ‘targeted’ extraction) of one or moreindividual compounds from a botanical feedstock. For example,controlling the density of solvent during the extraction process (e.g.by altering the temperature and/or pressure of solvent in a liquidand/or supercritical phase) may promote conditions in which thesolubility and/or rate of solution of one or more compounds (e.g., oneor more terpenes) present in the botanical material is relatively highin comparison with other compounds (e.g., other terpenes) present in thebotanical material. Under such conditions, one or more ‘targeted’compound class(es) may be dissolved by the solvent and drawn from thebotanical material in disproportionate quantities and/or at adisproportionate rate to other compounds present in the botanicalmaterial.

Another advantage of this design is that the cyclonic separation stagesmay each be configured or ‘tuned’ to preferentially separate certaincompounds from solvent. For example, a first cyclonic separator may beconfigured to preferentially remove a first ‘targeted’ extractedcompound(s) (e.g., one or more terpenes) from a solvent stream, and asecond cyclonic separator may be configured to preferentially remove asecond ‘targeted’ extracted compound(s) (e.g., other terpenes) from thesolvent. This may allow solvent containing certain targeted compound(s)to be directed to a cyclonic separator best suited to disassociate thosecompound(s) from solvent.

In accordance with this aspect, there is provided a method forextracting compounds from botanical material using apparatus comprisingan extraction chamber, a first cyclonic separation stage comprising atleast one first stage cyclonic separator, and a second cyclonicseparation stage comprising at least one second stage cyclonicseparator, the method comprising:

(a) introducing a feedstock of botanical material into the extractionchamber;

(b) operating the extraction chamber using a first solvent under a firstset of process conditions to preferentially extract a first compoundfrom the feedstock;

(c) conveying the first solvent containing the first extracted compoundfrom the extraction chamber to the first cyclonic separation stage alonga first solvent flow path;

(d) separating the first extracted compound from the first solvent inthe first cyclonic separation stage;

(e) operating the extraction chamber using a second solvent under asecond set of process conditions to preferentially extract a secondcompound from the feedstock;

(f) conveying the second solvent containing the second extractedcompound from the extraction chamber to the second cyclonic separationstage along a second solvent flow path; and,

(g) separating the second extracted compound from the second solvent inthe second cyclonic separation stage.

In any embodiment, the method may further comprise recycling the firstsolvent from the first cyclonic separation stage to the extractionchamber.

In any embodiment, the method may further comprise recycling the secondsolvent from the first cyclonic separation stage to the extractionchamber.

In any embodiment, the second solvent may be selected to be the same asthe first solvent.

In accordance with another aspect of this disclosure, which may be usedalone or in combination with one or more other aspects, a method forextracting compounds from botanical material using a condensable gassolvent includes conducting sequential extraction operations tosequentially extract heavier molecular weight compounds and conveyingthe solvent from the extraction operations sequentially though cyclonicseparation stages to sequentially obtain recovered extracts havinglighter molecular weights.

In accordance with this aspect, there is provided an apparatus for theextraction of compounds from botanical material, the apparatuscomprising:

-   -   (a) an extraction chamber;    -   (b) a first cyclonic separation stage comprising at least one        first stage cyclonic separator wherein the at least one first        stage cyclonic separator is configured to remove a first series        of extracted compounds having a first average molecular weight        from a solvent stream obtained from the extraction chamber;    -   (c) a first solvent flow path extending from the extraction        chamber to the first cyclonic separation stage;    -   (d) a second cyclonic separation stage comprising at least one        second stage cyclonic separator wherein the at least one second        stage cyclonic separator is configured to remove a second series        of extracted compounds from a solvent stream obtained from the        first cyclonic separation stage wherein the second series of        extracted compounds has a second average molecular weight that        is lower than the first average molecular weight; and,    -   (e) a second solvent flow path extending from the first cyclonic        separation stage to the second cyclonic separation stage.

In any embodiment, the apparatus may further comprise a third cyclonicseparation stage comprising at least one third stage cyclonic separatorwherein the at least one third cyclonic stage separator is configured toremove a third series of extracted compounds from a solvent streamwherein the third series of extracted compounds has a third averagemolecular weight that is lighter than the second average molecularweight; and, a third solvent flow path extending from the secondcyclonic separation stage to the third cyclonic separation stage.

In any embodiment, the solvent obtained from the extraction chamber mayrotate at a first speed in the at least one first stage cyclonicseparator and solvent obtained from the extraction chamber may rotate ata second speed in the at least one second stage cyclonic separatorwherein the second speed may be higher than the first speed.

In any embodiment, the solvent obtained from the extraction chamber mayrotate at a first speed in the at least one first stage cyclonicseparator, solvent obtained from the extraction chamber may rotate at asecond speed in the at least one second stage cyclonic separator whereinthe second speed may be higher than the first speed, and solventobtained from the extraction chamber may rotate at a third speed in theat least one third cyclonic separator wherein the third speed may behigher than the second speed.

In accordance with this aspect, there is also provided a method forextracting compounds from botanical material using apparatus comprisingan extraction chamber, a first cyclonic separation stage comprising atleast one first stage cyclonic separator, and a second cyclonicseparation stage comprising at least one second stage cyclonicseparator, the method comprising:

-   -   (a) introducing a feedstock of botanical material into the        extraction chamber;    -   (b) conducting a first extraction operation in which the        extraction chamber is operated using a solvent under a first set        of process conditions to preferentially extract a first compound        from the feedstock;    -   (c) subsequently conducting a second extraction operation in        which the extraction chamber is operated using the solvent under        a second set of process conditions to preferentially extract a        second compound from the feedstock wherein the second compound        has a higher molecular weight than the first compound;    -   (d) conveying the solvent from each extraction operation to the        first cyclonic separation stage and separating the first        extracted compound from the solvent in the first cyclonic        separation stage; and,    -   (e) conveying partially treated solvent obtained from the first        cyclonic separation stage to the second cyclonic separation        stage and separating the second extracted compound from the        partially treated solvent in the second cyclonic separation        stage.

In any embodiment, the method may further comprise obtaining fullyextracted solvent from the second cyclonic separation stage andrecycling the fully extracted solvent to the extraction chamber.

In any embodiment, the solvent obtained from the extraction chamber mayrotate at a first speed in the at least one first stage cyclonicseparator and the partially extracted solvent may rotate at a secondspeed in the at least one second stage cyclonic separator wherein thesecond speed may be higher than the first speed.

It will be appreciated by a person skilled in the art that an apparatusor method disclosed herein may embody any one or more of the featurescontained herein and that the features may be used in any particularcombination or sub-combination.

These and other aspects and features of various embodiments will bedescribed in greater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the described embodiments and to show moreclearly how they may be carried into effect, reference will now be made,by way of example, to the accompanying drawings in which:

FIG. 1 is a schematic view of an apparatus for the extraction ofcompounds from a botanical material in accordance with one embodiment;

FIG. 2 is a top schematic view of the extraction chamber, solvent flowpath, sonic flow nozzle, cyclone chamber, and cyclonic tangential fluidinlet of the apparatus of FIG. 1;

FIG. 3 is a cross-section view of the sonic flow nozzle of the apparatusof FIG. 1;

FIG. 4 is a cross-section view of the cyclonic separator of theapparatus of FIG. 1;

FIG. 5 is a schematic view of apparatus for the extraction of compoundsfrom a botanical material in accordance with another embodiment;

FIG. 6 is a simplified process flow diagram for a method for extractingcompounds from botanical material using a condensable gas solvent inaccordance with one embodiment;

FIG. 7 is a simplified process flow diagram for a method for extractingcompounds from botanical material using apparatus comprising anextraction chamber, a first cyclonic separation stage comprising atleast one first stage cyclonic separator, and a second cyclonicseparation stage comprising at least one second stage cyclonic separatorin accordance with one embodiment;

FIG. 8 is an image of a foamed extract exiting a cyclone chamber whereina sonic flow nozzle is not utilized; and,

FIG. 9 is an image of an extract obtained from a cyclone separatorwherein a sonic flow nozzle was utilized.

The drawings included herewith are for illustrating various examples ofarticles, methods, and apparatuses of the teaching of the presentspecification and are not intended to limit the scope of what is taughtin any way.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Various apparatuses, methods and compositions are described below toprovide an example of an embodiment of each claimed invention. Noembodiment described below limits any claimed invention and any claimedinvention may cover apparatuses and methods that differ from thosedescribed below. The claimed inventions are not limited to apparatuses,methods and compositions having all of the features of any oneapparatus, method or composition described below or to features commonto multiple or all of the apparatuses, methods or compositions describedbelow. It is possible that an apparatus, method or composition describedbelow is not an embodiment of any claimed invention. Any inventiondisclosed in an apparatus, method or composition described below that isnot claimed in this document may be the subject matter of anotherprotective instrument, for example, a continuing patent application, andthe applicant(s), inventor(s) and/or owner(s) do not intend to abandon,disclaim, or dedicate to the public any such invention by its disclosurein this document.

The terms “an embodiment,” “embodiment,” “embodiments,” “theembodiment,” “the embodiments,” “one or more embodiments,” “someembodiments,” and “one embodiment” mean “one or more (but not all)embodiments of the present invention(s),” unless expressly specifiedotherwise.

The terms “including,” “comprising” and variations thereof mean“including but not limited to,” unless expressly specified otherwise. Alisting of items does not imply that any or all of the items aremutually exclusive, unless expressly specified otherwise. The terms “a,”“an” and “the” mean “one or more,” unless expressly specified otherwise.

As used herein and in the claims, two or more parts are said to be“coupled”, “connected”, “attached”, or “fastened” where the parts arejoined or operate together either directly or indirectly (i.e., throughone or more intermediate parts), so long as a link occurs. As usedherein and in the claims, two or more parts are said to be “directlycoupled”, “directly connected”, “directly attached”, or “directlyfastened” where the parts are connected in physical contact with eachother. None of the terms “coupled”, “connected”, “attached”, and“fastened” distinguish the manner in which two or more parts are joinedtogether.

Furthermore, it will be appreciated that for simplicity and clarity ofillustration, where considered appropriate, reference numerals may berepeated among the figures to indicate corresponding or analogouselements. In addition, numerous specific details are set forth in orderto provide a thorough understanding of the example embodiments describedherein. However, it will be understood by those of ordinary skill in theart that the example embodiments described herein may be practicedwithout these specific details. In other instances, well-known methods,procedures, and components have not been described in detail so as notto obscure the example embodiments described herein. Also, thedescription is not to be considered as limiting the scope of the exampleembodiments described herein.

General Description of an Apparatus for the Extraction of Compounds FromBotanical Material

Referring to FIGS. 1 to 4, an exemplary embodiment of an apparatus forthe extraction of compounds from botanical material (which may bereferred to as a botanical feedstock and is preferably cannabis) isshown generally as 1000. The following is a general discussion of thisembodiment which provides a basis for understanding several of thefeatures which are discussed herein. As discussed subsequently, each ofthe features may be used individually or in any particular combinationor sub-combination in this or in other embodiments disclosed herein.

In the illustrated embodiment, the apparatus extracts compounds from abotanical feedstock (e.g. cannabis) using a condensable gas solvent.

In any of the embodiments disclosed herein, the solvent may be acondensable gas. Optionally, the solvent comprises carbon dioxide (CO₂).Use of CO₂ as a solvent may have one or more advantages. For example,carbon dioxide extraction may provide relatively pure, solvent-freeextracts, e.g. it may leave little or no residue in the extractedcompounds. It may also be characterized as an environmentally friendlyor ‘green’ alternative to other solvent-based extraction techniques.Also, the density of CO₂ can be altered by varying the pressure andtemperature, which may allow for selective extraction of one or moretargeted compounds. Also, the low viscosity of supercritical carbondioxide may allow it to penetrate into the botanical material moreeasily, while its diffusivity may allow for faster extractions.

Alternatively, the condensable gas solvent may include one or more of ahydrocarbon (such as ethane, propane, butane, cyclopropane, ethane),optionally a haloalkane, xenon, krypton, nitrous oxide, and sulfurhexafluoride. The selection of a particular condensable gas may beinfluenced by the strain of cannabis from which compounds are to beextracted, the particular compound or compounds targeted forpreferential extraction, and/or a targeted speed and/or efficiency ofthe extraction.

As exemplified in FIGS. 1 to 4, apparatus 1000 comprises at least oneextraction chamber 100 and at least one cyclonic separator 200. Asolvent flow path 300 extends from the extraction chamber to thecyclonic separator. In use, botanical material (e.g. cannabis) isexposed to solvent in the extraction chamber, under process conditionsthat result in one or more compounds (e.g., terpenes) present in thebotanical material being dissolved by the solvent and drawn from thebotanical material. Solvent containing the dissolved extractedcompound(s) is conveyed to the cyclonic separator via the solvent flowpath. At the cyclonic separator 200, the extracted compound(s) aredisassociated or separated from the solvent, and the extracted compoundsmay then be collected for use and/or further processing.

Extraction chamber 100 may be any extraction chamber and, optionally, anextraction chamber useable with a condensable gas and optionally, anextraction chamber operable at conditions at which a condensable gas isin a supercritical phase.

Extraction chamber 100 has at least one botanical feedstock port orinlet 110. Botanical feedstock port or inlet 110 is openable to allow abotanical feedstock to be introduced into and/or a botanical feedstockthat has been subjected to extraction to be removed from the interior ofthe extraction chamber. For example, feedstock inlet 110 may comprise afeedstock inlet port with an openable door 112.

In the illustrated schematic example, a single feedstock port 110 isprovided at a side of extraction chamber 100. It will be appreciatedthat in alternative embodiments, two or more ports 110 may be provided(e.g., an inlet port and a used feedstock removal port). Further, theport(s) may be placed elsewhere (e.g., on an upper and/or lower portionof the extraction chamber).

Extraction chamber 100 also has at least one solvent inlet through whichsolvent (e.g. a condensable gas solvent) may be introduced in to theextraction chamber. In the illustrated schematic example, a singlesolvent inlet port 120 is downstream of a source solvent. If the solventis a condensable gas solvent, then port 120 may be downstream of asource of pressurized solvent.

Any source of pressurized solvent may be used. For example, a tank 60 ofpressurized gas, a pump, or another suitable pressure control device(e.g. a diaphragm compression system). As exemplified, solvent inletport 120 is shown in communication with solvent pump 50, which is itselfin communication with a solvent reservoir (e.g. solvent tank 60).

If solvent is recycled, then as exemplified, a solvent return conduit 40may be provided through which solvent may be recycled back to theextraction chamber (as discussed further below), either directly orthrough tank 60.

It will be appreciated that in alternative embodiments, two or moresolvent inlets may be provided. For example, the downstream end ofreturn conduit 40 may be in communication with tank 60 or may beconveyed directly to extraction chamber 100 (such as by a separatepump).

During operation of the extractor, solvent pump 50 or another suitablepressure control device (e.g. a diaphragm compression system) may beused in controlling process conditions of the solvent in the extractionchamber. For example, solvent pump 50 may be used to control thepressure of solvent within the extraction chamber, which may assist inbringing solvent to a desired phase (e.g. liquid, supercritical fluid)and/or a desired density, and in maintaining solvent at a desired phaseand/or desired density. Preferably, the pressure control system allowsthe extraction chamber pressure to be selectively varied across anoperational range of about ambient to about 5,000 psi, and may be from800 to 5,000 psi, 1,000 to 4,000 psi, 1,500 to 3,500 psi and 2,000 psito 3,000 psi. Examples of operating pressure ranges of extractionchamber 100 may be from 800 to 1,000 psi, from 1,000 to 1,200 psi, from1,200 to 1,400 psi, from 1,400 to 1,800 psi, from 1,800 to 2,000 psi, orfrom 2,000 to 4,000 psi.

Optionally, as exemplified, extraction chamber 100 may have one or moreheat transfer members 135 that may be used to control the temperature ofthe interior of the extraction chamber by adding thermal energy toand/or removing thermal energy from, the interior of the chamber. Forexample, heat transfer member 135 may include a heating jacket throughwhich fluid may be circulated to raise or lower the temperature ofportions of the chamber wall. Alternatively, or additionally, heattransfer member 135 may include electrical heat tracing bonded (e.g.directly bonded) to an exterior surface of the extraction chamber. Asthe extractor vessel may need to be heated and cooled to maintaindesired operating conditions, the use of electrical heat tracing wouldrequire a cooling system if the extractor is also to be cooled.

During operation of the extractor, heat transfer member 135 may be usedin controlling process conditions of e.g. solvent in the extractionchamber. For example, heat transfer member 135 may be used to controlthe temperature of solvent within the extraction chamber, which mayassist in bringing solvent to a desired phase (e.g. liquid,supercritical fluid) and/or a desired density, and in maintaining thesolvent at a desired phase and/or desired density. Preferably, heattransfer member 135 may allow the extraction chamber temperature to beselectively varied across an operational range of from about −20° C. toabout 110° C. and may be from 0 to 90° C., from 20 to 70° C., and from20-50° C. Examples of operating temperature ranges of extraction chamber100 may be from −20° C. to 0° C., from 0° C. to 20° C., from 20° C. to50° C., from 50° C. to 110° C., from 50 to 70° C., or from 70 to 90° C.

It will be appreciated that if the solvent is a condensable gas solvent,then the solvent may be introduced into extraction chamber 100 as aliquid or in a supercritical phase, or may be changed to be a liquid orat a supercritical phase once introduced into the extraction chamber.For example, if the solvent is introduced as a liquid, it may besubjected to conditions in the extraction chamber which result in thesolvent transitioning to a supercritical phase.

An advantage of providing an extraction chamber that can be operated attemperatures, e.g., from about −20° C. to about 110° C. and at, e.g.,pressures of up to about 4,000 psi it that such an extraction chambermay allow the flexibility to run extractions across the most variableregions of the phase space of CO₂, spanning gas, liquid, andsupercritical.

In some embodiments, heat transfer member 135 may also be used tocontrol the temperature of botanical feedstock positioned in theextraction chamber. For example, after being introduced into thechamber, botanical material may be cooled until some, substantially all,or all of the water in the botanical material transitions to a solidphase (i.e. the material may be frozen or partially frozen). Forexample, at least 50%, 60%, 70%, 80% or 90% of the water in thefeedstock may be in a solid phase. Alternatively, botanical materialintroduced into the extraction chamber in a frozen or partially frozenstate may be maintained in such a state using heat transfer member 135.

An advantage of freezing the botanical material is that this may impedeor prevent water in the botanical material from being dissolved by thesolvent. This may result in a more ‘complete’ extract being obtained,and may also improve the speed and/or efficiency of the solventextraction.

Another advantage of freezing the botanical material is that this mayreduce or obviate the need to desiccate the material prior toextraction. This may be particularly advantageous for extractingcompounds (e.g., terpenes) from a cannabis feedstock. For example, thismay allow cannabis to be harvested and introduced into the extractionchamber without undergoing a drying process to remove moisture from thecannabis feedstock, or only undergoing an abbreviated drying process.

For example, cannabis having a moisture content above about 12%, orabove about 9%, may be characterized as being ‘fresh’ or ‘undried’cannabis. As drying cannabis may be a relatively lengthy process, andmay involve a dedicated drying room or other specialized dryingapparatus, the ability to extract compounds from ‘fresh’ cannabis mayresult in overall process efficiencies, reduced process time, and/orcost savings.

Also, one or more compounds typically present in cannabis may be lost,damaged, or otherwise adversely affected during a typical dryingprocess.

For example, volatile terpenes and aldehydes may be consideredparticularly susceptible to loss during drying. Accordingly, extractionsperformed with an undried feedstock or even a feedstock that has onlypartially been dried may facilitate a greater extraction and recovery ofthese compounds.

As exemplified in FIG. 1, a conduit 30 provides a flow path for solventto flow from the extraction chamber 100 to the cyclonic separator 200.As exemplified, conduit 30 extends between a solvent outlet 130 of theextraction chamber 100 and a fluid inlet 210 of the cyclonic separator200.

As exemplified, one or more heat transfer members 35 may be providedalong at least a portion of the solvent flow path between solvent outlet130 of the extraction chamber 100 and a fluid inlet 210 of the cyclonicseparator 200. The heat transfer member 35 may be any heat transfermember used to transfer heat between the member 35 and the solvent inthe flow path.

Accordingly, the heat transfer member 35 may be used to control thetemperature of solvent by adding thermal energy to, or removing thermalenergy from, solvent flowing through the conduit.

Typically, heat is added to the solvent in the flow path to convert thesolvent to a supercritical or gaseous phase. When the heat transfermember 35 is used to heat solvent flowing through the solvent flow path,the location(s) at which a heat transfer device is provided may becharacterized as a ‘heating zone’.

It will be appreciated that any heat transfer member 35 may be used. Theheat transfer member may be a heat exchanger, such as a cross flow heatexchanger or an in-line heat transfer member. For example, a heatingjacket may be provided on part of the conduit 30. Alternatively, oradditionally, heat transfer member 35 may include electrical heattracing bonded (e.g. directly bonded) to an exterior surface of theconduit.

It will be appreciated that heat transfer member 35 may be located atany location along conduit 30. Optionally, the heat transfer member 35may be located towards the downstream end of conduit 30, such as one ormore of proximate fluid inlet 210 of the cyclonic separator, as part offluid inlet 210 of the cyclonic separator, immediately upstream of fluidinlet 210 of the cyclonic separator, and immediately upstream of a sonicflow nozzle. An advantage of positioning the heat transfer member 35closer to the entrance to the cyclone separator is that the solvent maybe maintained in a liquid or supercritical phase for most or all of thelength of conduit 30. Liquid and supercritical states have bettersolubilization characteristics than gaseous solvent. Further, when thesolvent converts to the gaseous state, extracted botanical elements,which may be oily, may separate from the solvent and may foul conduit 30and other parts of the flow path. Accordingly, maintaining the solventin a liquid or supercritical phase for longer may reduce fouling of theflow path.

It will be appreciated that one or more control valves or other flowcontrol devices may be positioned in the solvent flow path to assist incontrolling process conditions, e.g., flow rate and/or the temperatureof the solvent entering the cyclonic separator, between the extractionchamber 100 and the cyclonic separator 200. Additionally, oralternatively, one or more sensors, such as temperature sensors (e.g. athermocouple, resistive thermal device, and the like) and/or pressuresensors (e.g. a quartz-based sensor, electrical resonating diaphragm,and the like) may be positioned along the solvent flow path, e.g. toprovide data to a process control system, such as a SCADA control systemor the like.

Cyclone separator has a tangential fluid inlet 210. Any tangentialcyclone inlet may be used. Accordingly, fluid inlet 210 may bepositioned and constructed in any manner suitable for directing solventtangentially into cyclone chamber 205. Optionally, two or moretangential inlets may be spaced around the circumference of the cyclonechamber, which may facilitate cyclonic rotation of solvent within thecyclone chamber.

Cyclone separator 200 may be any cyclone separator known in theseparation arts. As exemplified in FIG. 1, cyclone separator 200 has afluid inlet 210 and a fluid outlet 220 at the upper end of the cycloneseparator 200 and a separated material outlet 230 at the lower end ofthe cyclone separator 200. In use, solvent may enter the cyclone chamber205 of FIG. 1 tangentially through the fluid inlet 210, and swirl (e.g.move cyclonically) in the cyclone chamber to promote separation ofcompounds extracted from the botanical material from the solvent.Solvent from which the compound(s) have been separated may exit thecyclone chamber 205 through a gas outlet 220 provided at an upper end ofthe cyclone separator 200. The separated compound(s) may exit thecyclone chamber 205 through the separated material outlet 230 providedat a lower end of the cyclone separator.

Optionally, as exemplified in FIG. 1, apparatus 1000 may also include anozzle 300 positioned adjacent (e.g., immediately upstream of or as partof) tangential fluid inlet 210 of cyclone chamber 205. In theillustrated example of FIG. 2, tangential fluid inlet 210 is positioneddirectly downstream of (e.g., abutting) an outlet 320 of nozzle 300.Such an arrangement may allow solvent exiting flow nozzle 300 to bedirectly tangentially introduced into the cyclonic tangential fluidinlet 210 and/or the cyclone chamber 205. In some embodiments, thecyclonic tangential fluid inlet 210 may comprise the nozzle 300.

Optionally, nozzle 300 accelerates the solvent passing therethrough(such as a convergent nozzle) and may be a sonic flow nozzle (such as aconverging-diverging nozzle). In alternative embodiments, flow nozzle300 may comprise an orifice plate. A cross-section of an example of anozzle 300 is illustrated in FIG. 3. As exemplified, nozzle 300 has aninlet end 310 and an outlet end 320. The internal diameter of the nozzlenarrows in the direction of flow, from an inlet diameter 315 at theinlet end to a smaller diameter 335 at the nozzle throat 330. Downstreamof the throat 330, the diameter increases. As exemplified, the wall 340at the outlet of the throat 330 is generally transverse to the directionof flow through the nozzle. The diameter of the nozzle thereforeimmediately increases to a diameter 325 which is larger than throatdiameter 335 and may be about the same as inlet diameter 315. It will beappreciated that wall 340 may extend in the direction of flow at anangle of less than 90° (which is exemplified in FIG. 3). Fluid exitingthroat 330 expands at a dispersion angle A of from 90° to 70°, from 85°to 70°, from 80° to 70°, or from 75° to 70°.

The nozzle 300 may be positioned and configured such that fluid exitingoutlet 320 of nozzle 300 may enter into the cyclone chamber withoutimpinging on an interior wall 345 of the downstream part of nozzle 300and/or tangential fluid inlet 210. Alternatively, fluid may only impingeon a downstream part of the interior wall 345 of the downstream part ofnozzle 300 and/or the tangential fluid inlet 210. For example, thedispersion angle A may be selected such that fluid exiting nozzle 320will not impinge upon the wall of the tangential inlet. It will beappreciated that wall 345 may define part or all of the tangentialinlet. An advantage of design is that separation of compound(s) from thesolvent in the flow stream downstream of throat 330 may reduce orprevent an accumulation of separated compounds within the nozzle and/ortangential inlet.

In use, the apparatus is preferably operated under process conditions inwhich the nozzle operates in a ‘choked’ state. For example, a ratio ofthe pressure of the fluid entering the nozzle inlet (which may bereferred to as the “nozzle inlet pressure” or “upstream pressure”) andthe pressure of the fluid exiting the nozzle outlet (which may bereferred to as the “nozzle outlet pressure” or “downstream pressure”) ispreferably greater than 1.4 and may be from 1.4:1 to 14.2:1, from 1.4:1to 7.2:1, from 4.2:1 to 14.2:1. Examples of operating ranges that may beused are 1.4:1 to 4.2:1, from 4.2:1 to 7.2:1, from 7.2:1 to 14.2:1. Anadvantage of operating the flow nozzle under ‘choked’ conditions is thatthe mass flowrate through the nozzle is only influenced by the upstreampressure and upstream temperature (i.e. density) of fluid entering thenozzle. Accordingly, upstream pressure disturbances (e.g. pressurepulsation due to pumps, flow fluctuations as a result of extraction,etc.) may be inhibited or prevented from moving downstream past thenozzle 300 and into the cyclonic separator, and thus may be inhibited orprevented from causing undesirable pulsations and/or vortex flowinstabilities during the decompression and/or separation that occurs inthe cyclonic separator.

By providing a sonic flow nozzle 300, solvent passing through the nozzlemay enter the cyclone chamber at sonic or supersonic velocity. Anadvantage of this design is that the radial acceleration resulting fromthe solvent being rotated in the cyclone chamber while travelling atsonic or supersonic velocities may be more effective at promotingdisassociation (i.e. separation) of extracted compound(s) from thesolvent, as compared to sub-sonic flow. For example, in typicalgas-liquid cyclonic separators (e.g. with sub-sonic fluid injection),there may be significant ‘carry over’ of entrained product exiting theseparator along with the solvent exiting the cyclone outlet, which maylead to fouling of e.g. low pressure piping and compression pumpspositioned downstream of the cyclone gas outlet. Further, the separatedmaterial tends to be foamed with entrained solvent as exemplified inFIG. 8.

Optionally, as exemplified in FIG. 1, the cyclone separator 200 includesa temperature control system, which in the illustrated example is shownas a heat transfer member 235 such as a heat jacket 235. Alternatively,or additionally, heat transfer member 235 may include electrical heattracing bonded (e.g. directly bonded) to an exterior surface of thecyclone separator 200. Heating jacket 235 may be used to convey thermalenergy to the interior wall 215 of the cyclone chamber 205. Heating thecyclone chamber may have one or more advantages. For example, compoundsseparated from the solvent in the cyclone separator that come intocontact with the interior wall of the cyclone separator may thereby beheated, which may reduce the viscosity of the separated compounds. Anadvantage of reducing the viscosity of the separated compounds is thatthey may more easily and/or rapidly flow down the walls of the cycloneseparator (due to gravity) to a collection chamber, such as collectionchamber 240.

Separated material exiting separated material outlet 230 may becollected in any manner known in the separation arts. As exemplified inFIG. 1, a separated material collection chamber 240 in communicationwith the separated materials outlet 230 of cyclonic separator 200 may beprovided to receive compounds disassociated (i.e. separated) fromsolvent entering fluid inlet 210 of the cyclonic separator 200.

Preferably, the separated material collection chamber 240 is removablefrom the cyclonic separator 200. Providing a detachable separatedmaterial collection chamber 240 may allow a user to transport (e.g.carry) the collected separated material (e.g. compound(s) extracted fromcannabis) to another location for emptying and/or further processing,without needing to carry or move the cyclonic separator 200. Preferably,the separated material collection chamber 240 is removable as a closedmodule, which may help prevent the extracted compounds from spilling outof the separated material collection chamber 240 during transport.

Alternatively, the separated materials outlet 230 may be in flowcommunication with (connected or removably connected to) a conduit whichtransports the separated compound(s) to, e.g., another piece ofequipment for further processing.

As exemplified in FIG. 1, a gas return conduit 40 may optionally beprovided between a gas outlet 220 of the cyclone separator and a solventinlet 120 to the extraction chamber 100. An advantage of this design isthat it may allow the gas solvent to be recycled to the extractionchamber 100 after extracted compounds have been disassociated from thesolvent in the cyclone chamber.

This may be characterized as a ‘closed-loop’ system. Optionally, one ormore gas pumps 55 or other flow control devices may be provided tore-pressurize the solvent prior to its reintroduction to the extractionchamber and/or a storage tank, such as tank 60. An advantage ofrecycling solvent (e.g. CO₂) is that such a closed loop system mayreduce solvent usage, and may therefore be characterized as a lowconsumption, environmentally friendly, and/or ‘green’ process.Alternatively, such a solvent recycling system may not be provided, andsolvent exiting the cyclone separator may be expelled or stored, withoutbeing recycled back to the extraction chamber.

In one embodiment, the apparatus includes both a heat transfer member 35and a nozzle 330. The heat transfer member 35 is located immediatelyupstream from nozzle 300. Accordingly, solvent entering the nozzle 300may be gaseous. An advantage of this design is that the solvent may bemaintained in a liquid or supercritical phase until just before itenters nozzle 300 and may then enter the cyclone chamber with no or onlyminimal impingement on the wall of the flow path downstream of nozzle300, thereby limiting or preventing the fouling of the flow pathdownstream of nozzle 300.

General Description of a Method for Extracting Compounds From BotanicalMaterial Using a Condensable Gas Solvent

The flowing is a description of a method for extraction which may beused by itself or in combination with one or more of the other featuresdisclosed herein including the use of any of the features of theapparatus and/or and any of the methods disclosed herein.

Referring to FIG. 6, there is illustrated a method 500 for extractingcompounds from botanical material using a condensable gas solvent.Method 500 may be performed using apparatus 1000 or any other suitableapparatus for the extraction of compounds from a botanical material.FIG. 6 exemplifies a method in which a single extraction operation isconducted and a single cyclone separator is used. As discussed herein,the same feedstock may be subjected to two or more extractionoperations, which may be conducted at the same conditions or atdifferent conditions, and each extraction operation may use the samesolvent or a different solvent. Further, as also discussed herein, anextraction operation or a series of extraction operations, may use twoor more cyclone separators. It will be understood that the methodexemplified in FIG. 6, with any one or more of the optional steps, maybe used with a method employing multiple extraction steps and/ormultiple cyclone separators.

At 505, in an extraction chamber, such as extraction chamber 100, acondensable gas solvent is used to extract at least one compound from afeedstock of botanical material. For example, the botanical material(e.g.

cannabis) may be introduced into chamber 100 through a feedstock inlet110 provided at the end of chamber 100. Once the botanical material hasbeen introduced and the feedstock inlet closed, a condensable gassolvent (e.g. carbon dioxide) may be introduced into the extractionchamber, and process conditions within the extraction chamber (pressure,temperature, etc.) may be controlled so that the botanical material isexposed to solvent at a predetermined state (phase, density,temperature, pressure, etc.) for a predetermined time, during which oneor more compounds present in the botanical material are dissolved by thesolvent and extracted from the botanical material. It will beappreciated that the condensable gas may be introduced into chamber 100at the predetermined state and the conditions in chamber 100 maymaintain the condensable gas in the predetermined state. The extractionchamber may be at any pressure and temperature discussed herein

The condensable gas may be used to extract one or more compounds fromthe feedstock. Optionally, if the botanical material is cannabis,compounds extracted by the solvent may include one or more of analiphatic aldehyde (e.g. nerol, geraniol, octanal, decanal), a terpene(e.g. limonene, pinenes, ocimenes), and a cannabinoid.

Optionally, in any embodiment, a fresh feedstock of cannabis may beobtained and introduced into extraction chamber 100. For example,cannabis may be harvested and introduced into the extraction chamberwithout undergoing a drying process to remove moisture from the cannabisfeedstock.

Optionally, in any embodiment, a cannabis feedstock (fresh or dried) maybe comminuted prior to being introduced into the extraction chamber inorder to increase the surface area of the botanical material.

Optionally, in any embodiment, a feedstock of fresh cannabis may beprovided to an extraction chamber where water in the feedstock is in asolid phase (which may be characterized as frozen or partially-frozencannabis). Alternatively, unfrozen cannabis may be provided toextraction chamber 100, and the temperature of the extraction chamber100 brought to and/or maintained at a temperature below the freezingpoint of water (e.g. using heat transfer member 135) until water in thefeedstock transitions to the solid phase.

Optionally, in any embodiment, condensable gas solvent in the extractionchamber may be brought to and/or maintained in at least one of a liquidphase and a supercritical phase, and used to extract at least onecompound from the cannabis while in a liquid and/or supercritical phase.For example, process conditions within the extraction chamber (pressure,temperature, etc.) may be controlled so that solvent in a liquid phaseand/or in a supercritical phase contacts the botanical feedstock for apredetermined time, during which one or more compounds present in thefeedstock are dissolved by the solvent and extracted from the feedstock.

At 510, solvent containing the dissolved or extracted one or morecompounds is withdrawn from the extraction chamber and the solvent(which may be characterized as a ‘solvent stream’) is then conveyedthrough a solvent flow path to a separator. For example, solvent may bewithdrawn from extraction chamber 100 via solvent outlet port 130, andconveyed to fluid inlet 210 of cyclonic separator 200 through solventconduit 30.

Optionally, at 515, at least some solvent may be converted to a gaseousphase upstream of the cyclone chamber. For example, the solvent streammay be heated prior to entering the separator. For example, heatingjacket 35 or another heating member may be used to heat solvent as itpasses through the solvent flow path. Heating the solvent may causesome, a substantial portion of, or all (e.g., more than 50%, 60%, 70%,80%, or 90%) of the solvent in a liquid phase to transition to a gaseousphase and/or to a supercritical phase.

Alternatively, or additionally, the pressure of the solvent streamupstream of the cyclone chamber may be lowered, e.g. via one or morecontrol valves positioned in the solvent flow path. Reducing thepressure of the solvent stream may cause some, a substantial portion of,or all (e.g., more than 50%, 60%, 70%, 80%, or 90%) of any liquidsolvent to transition to a supercritical and/or gaseous phase. Also,reducing the pressure may cause some, a substantial portion of, or all(e.g., more than 50%, 60%, 70%, 80%, or 90%) of any supercriticalsolvent to transition to a gaseous phase.

Optionally, at 520, solvent traveling at sonic or supersonic velocitymay be obtained. For example, a sonic flow nozzle 300 may be positionedin the solvent flow path upstream of the fluid inlet to the cyclonechamber, and the nozzle inlet pressure, nozzle outlet pressure, and/ornozzle backpressure may be adjusted so that most or substantially all ofthe solvent exits the sonic flow nozzle at sonic or supersonic velocity.Advantageously, this may allow solvent to be directed into a cyclonechamber at sonic or supersonic velocity. Optionally, the solvent may beheated immediately upstream of the nozzle 300.

At 525, some, or preferably most, or more preferably substantially allof the extracted compound(s) is separated from the solvent. For example,the solvent stream may be directed into a cyclonic separator, such ascyclonic separator 200.

Preferably, solvent is introduced tangentially into a cyclone separator,e.g. via a tangential cyclone inlet, such as tangential cyclone inlet210. Optionally, if a nozzle 300 is utilized, the nozzle may bepositioned immediately upstream of a tangential cyclone inlet or nozzle300 may be the tangential cyclone inlet. Accordingly, solvent may beintroduced directly into the cyclone separator, i.e. without beingdirected through a conduit or the like between a nozzle outlet and thecyclone separator. For example, the outlet of the nozzle 300 may bepositioned adjacent the cyclone separator, and solvent exiting the sonicflow nozzle may be directed so as to avoid contacting sidewalls of aconduit downstream of the nozzle 300 and/or an inlet port of the cycloneseparator.

As another example, the outlet of the sonic flow nozzle may bepositioned at an inlet port of the cyclone separator, and solventexiting the sonic flow nozzle may be conveyed immediately into thecyclone separator so as to avoid contacting the inlet port of thecyclone separator.

An advantage of introducing solvent directly into the cyclone separatorwhen the solvent has been converted to a gaseous state is that it mayinhibit fouling of the sidewalls of a conduit downstream of the nozzle300 by an extract that is liberated from the solvent when it becomesgaseous.

Optionally, at 530, some, or preferably most, or more preferablysubstantially all of the at least one compound dissolved in the solventmay be separated in the cyclone separator and collected as an unfoamedliquid as exemplified in FIG. 9. For example, if the botanical materialis cannabis, compounds separated from the solvent in the cycloneseparator may include one or more of an aliphatic aldehyde, a terpene,and a cannabinoid.

An advantage of collecting the separated at least one compound as anunformed liquid is that the collected liquid may be easier to work withand/or easier to post-process.

Optionally, at 535, the cyclone separator may be heated. For example, atemperature control system such as heating jacket 235 or the like may beused to convey thermal energy to the interior wall of the cycloneseparator during operation of the cyclone separator. The cycloneseparator may be heated to raise the temperature of the cyclone chamberto a predetermined temperature prior to the separation operation.Alternately or in addition, the temperature control system may be usedto maintain the temperature of the cyclone chamber at a predeterminedtemperature during operation. For example, if a sonic flow nozzle isutilized, the expansion of the solvent may cool the solvent stream whichenters the cyclone chamber. The temperature control system may partiallyor fully counter the cooling effect of the flow through a sonic flownozzle and may therefore enable the cyclone separator to operate at adesign temperature or temperature range. Thus, compounds separated fromthe solvent in the cyclone separator may thereby be heated or maintainedat a design temperature or temperature range, which may reduce theviscosity of the separated compounds. An advantage of reducing theviscosity of the separated compounds is that they may more easily and/orrapidly flow down the walls of the cyclone separator (due to gravity) toa collection chamber, such as collection chamber 240.

Apparatus for the extraction of compounds from botanical material withmultiple cyclonic separation stages

Referring to FIG. 5, an exemplary embodiment of another apparatus forthe extraction of compounds from botanical material is shown generallyas 2000. Elements having similar structure and/or performing similarfunction as those in the example apparatus illustrated in FIGS. 1 to 4are numbered similarly, and will not be discussed further. Asexemplified therein, an extraction and separation operation may use twoor more cyclone separators.

As exemplified in FIG. 5, apparatus 2000 includes an extraction chamber100, a first cyclonic separator 200A, a second cyclonic separator 200B,and a third cyclonic separator 200C. While in the illustrated examplethree cyclonic separators are shown, in alternative embodimentsapparatus 2000 may have only two cyclonic separators, or four or morecyclonic separators may be provided.

Providing an apparatus 2000 with two or more cyclonic separators inparallel may have one or more advantages. For example, each cycloneseparator may be configured to disassociate different compounds from asolvent flow. For example, different cyclone separators may beconfigured to induce different rotational velocities. Higher rotationalvelocity may be used to separate smaller droplets of liquid or smallerparticles containing higher molecular weight compounds which may beseparated from a flow stream of solvent in a cyclone. Accordingly, afirst cyclone separator may produce a lower rate of rotation of solventwhich will result in heavier (larger) droplets of liquid or largerheavier particles being separated than in a second stage cycloneoperating at a higher rotational speed. However, the velocity in thefirst cyclone separator may be insufficient to disentrain lighter(smaller) droplets of liquid or lighter compounds. A second downstreamcyclone separator may be operated to produce a higher rotationalvelocity, which may remove the lighter (smaller) droplets of liquid orlighter compounds. Providing the ability to selectively direct solventfrom the extraction chamber to one of two or more cyclonic separators,which may be in series, may facilitate a more complete disassociation ofextracted compound(s) from solvent, as solvent containing particularcompound(s) can be directed to a separator best suited to disassociatethat compound(s). For example, the solvent stream may be sequentiallydirected though the two or more cyclones (e.g., they may be operated inseries). Alternately, different extraction operations may be conductedto selectively remove certain compounds from a feedstock. Therefore, oneextraction operation may produce a solvent having heavier compounds anda second extraction operation may produce a solvent having lightercompounds.

The solvent from each extraction operation may be directed to adifferently configured cyclone (e.g., each cyclone may be configured toseparate compounds targeted by a particular extraction operation).

Returning to FIG. 5, in use, botanical material (e.g. cannabis) may beexposed to solvent in the extraction chamber 100 under a first set ofprocess conditions to preferentially extract a first set of one or morecompounds present in the botanical material from the botanical material.Solvent containing the first extracted compound(s) may be conveyed tothe first cyclonic separator 200A, where the first extracted compound(s)are disassociated from the solvent. Subsequently, the botanical materialmay be exposed to the same or a different solvent in the extractionchamber 100 under a second set of process conditions to preferentiallyextract a second set of one or more compounds from the botanicalmaterial. Solvent containing the second extracted compound(s) may thenbe conveyed to the second cyclonic separator 200B, where the secondextracted compound(s) are disassociated from the solvent. Optionally,the botanical material may subsequently be exposed to solvent in theextraction chamber 100 under a third set of process conditions topreferentially extract a third set of one or more compounds from thebotanical material. Solvent containing the third extracted compound(s)may then be conveyed to the third cyclonic separator 200C, where thethird extracted compound(s) are disassociated from the solvent.

Preferably, each cyclonic separator may be configured based on theextracted compound(s) expected to be in the solvent flow, which mayresult in a more thorough and/or efficient disassociation or separationof the compounds from the solvent. For example, if a first set ofprocess conditions of the extractor is designed to preferentially targetone or more high-molecular weight compounds for extraction, the firstcyclonic separator may be configured to optimize the removal of highermolecular weight compounds from solvent. Similarly, if a second set ofprocess conditions of the extractor is designed to preferentially targetone or more lower-molecular weight compounds for extraction, the secondcyclonic separator may be configured to optimize removal of lowermolecular weight compounds from solvent. For example, during separation,solvent in cyclone chamber 205A of cyclone separator 200A may rotate ata first speed, and solvent in cyclone chamber 205B of cyclone separator200B may rotate at a second, different speed.

For example, if the botanical material is cannabis and the extractionchamber is operated under a set of process conditions to preferentiallyextract one or more waxes from the cannabis, solvent containing the oneor more extracted waxes may be directed to a cyclonic separator that isoperated at pressure conditions to separate this class of compounds. Forexample, under extraction conditions that result in a high CO₂ density(which may be any combination of pressure and temperature that resultsin the CO₂ being in a high density state, such as over 0.85 g/cm³),waxes may be solubilized and extracted.

Solvent containing the waxes may be directed to one or more separatorswherein the CO₂ is expanded to drop out the solute and the gaseous CO₂which is obtained may be returned to a compression system and recycledinto the extractor.

If the extraction chamber is operated under a set of process conditionsto preferentially extract one or more light oils from the cannabis,solvent containing the one or more extracted light oils may be directedto a cyclonic separator to expand and deposit the solute and return thedecompressed CO₂ back to, e.g., a pump for recompression and recycleinto the extractor. For example, lighter compounds may be selectivelyextracted by using the CO₂ in a low density supercritical state, forexample, the density of the solvent may be between 0.25 to 0.35 g/cm³.Such density conditions may be obtained using a number of combinationsof pressure and temperature, with the caveat that the temperature beabove the critical temperature of 31.1° C., preferably greater than 33°C. to avoid critical point instabilities.

It will be appreciated that the lighter oils and the waxes may besequentially extracted. In such a case, the extraction operations areoptionally conducted so as to initially extract the lighter molecularweight compounds (e.g., the lighter oils) and to then extract theheavier molecular weight compounds (e.g., the waxes). The solvent fromthe lighter oil extraction operation may be directed to one or morecyclone separators that operate in parallel and which are designed toseparate the lighter oils from the solvent. The solvent from the waxextraction operation may be directed at one or more cyclone separatorsthat operate in parallel and which are designed to separate the waxesfrom the solvent.

Alternatively, a plurality of cyclone stages may be provided in series,wherein each cyclone stage may comprise one or more cyclone separatorsoperating in parallel. The solvent from each extraction stage may bedirected sequentially through the plurality of cyclone stages. In such acase, the first stage cyclone separator(s) may be designed to separatethe heavier compounds (e.g., compounds having a heavier molecularweight) and the second stage cyclone separator(s) may be designed toseparate the lighter compounds (e.g., compounds having a lightermolecular weight). It will be appreciated that three or more cyclonestages may be employed, each using one or more cyclone separators inparallel, wherein each stage recovers lighter compounds than theprevious stage.

In an alternative use of apparatus 2000, botanical material (e.g.cannabis) may be exposed to solvent in the extraction chamber 100 undera set of process conditions to extract a relatively large range ofcompounds, and solvent containing the extracted compound(s) may beconveyed to the first cyclonic separator 200A to preferentiallydisassociate a first set of compounds from the solvent. Next, while theextraction chamber may still being operated under the same set ofprocess conditions, solvent containing the extracted compound(s) maysubsequently be conveyed to the second cyclonic separator 200B topreferentially disassociate a second set of compounds from the solvent.

In the illustrated example, a conduit 32 provides a path for solvent toflow from the extraction chamber 100 to a valve 80. Valve 80 may be usedto selectively direct solvent from conduit 32 to first cyclonicseparator 200A (via conduit 34), second cyclonic separator 200B (viaconduit 36), or third cyclonic separator 200C (via conduit 38).Alternative embodiments may include different solvent flow paths and/orvalve configurations. For example, in the illustrated example, conduit32 is common to the solvent flow paths from the extraction chamber toeach cyclonic separator, and may therefore be characterized as a commonsolvent flow path portion. Alternatively, apparatus 2000 may not have acommon solvent flow path portion, e.g. by providing separate dedicatedconduits from the extraction chamber to each cyclonic separator, whereineach conduit may have an associated valve to selectively direct solventflow from the extractor to its respective cyclonic separator.

As with the embodiment of FIGS. 1-4, an optional heat transfer device 35and/or nozzle 300 may be provided along at least a portion of one ormore and optionally each solvent flow path, providing each solvent flowpath with a ‘heating zone’, as discussed above.

It will be appreciated that one or more control valves or other flowcontrol devices may be positioned in the solvent flow paths to assist incontrolling process conditions between the extraction chamber 100 andeach cyclonic separator 200A, 200B, 200C. Additionally, oralternatively, one or more sensors, such as temperature sensors (e.g. athermocouple, resistive thermal device, and the like) and/or pressuresensors (e.g. a quartz-based sensor, electrical resonating diaphragm,and the like) may be positioned along the solvent flow path(s), e.g. toprovide data to a process control system.

As with the embodiment of FIGS. 1-4, apparatus 2000 may also includeflow nozzles 300A, 300B, and 300C positioned adjacent the fluid inlet210A, 210B, and 210C of each cyclone separator 200A, 200B, 200C,respectively. Preferably, each flow nozzle 300 is configured to allowsolvent exiting that flow nozzle to be directly tangentially introducedinto its corresponding cyclone chamber. Each flow nozzle 300A, 300B, and300C may be a sonic flow nozzle, such as a convergent nozzle or aconverging-diverging nozzle, or an orifice plate or other nozzle.

As exemplified in FIG. 5, separated material collection chambers 240A,240B, 240C are shown in communication with the separated materialsoutlets 230A, 230B, 230C of cyclonic separators 200A, 200B, 200C,respectively, to receive compounds disassociated (i.e. separated) fromsolvent using each cyclonic separator.

Preferably, each separated material collection chamber 240A, 240B, 240Cis removable from its respective cyclonic separator 200A, 200B, 200C(e.g. as a closed module). Alternatively, one or more of the separatedmaterials outlets 230A, 230B, 230C may each be in flow communicationwith a conduit which transports the separated compound(s) to, e.g.,another piece of equipment for further processing.

General description of another method for extracting compounds frombotanical material using a condensable gas solvent

The flowing is a description of a method for extraction which may beused by itself or in combination with one or more of the other featuresdisclosed herein including the use of any of the features of theapparatus and/or and any of the methods disclosed herein. The method maybe conducted using a solvent stream obtained from any extractionprocess.

Referring to FIG. 7, there is illustrated a method 600 for extractingcompounds from botanical material using apparatus comprising anextraction chamber, a first cyclonic separation stage comprising atleast one cyclonic separator, and a second cyclonic separation stagecomprising at least one cyclonic separator. Method 600 may be performedusing apparatus 2000 or any other suitable apparatus for the extractionof compounds from a botanical material.

At 605, a feedstock of botanical material is introduced to an extractionchamber. For example, a feedstock of cannabis may be introduced toextraction chamber 100 through a feedstock inlet 110 of chamber 100. Asdiscussed above, optionally a fresh feedstock of cannabis (e.g. cannabishaving a moisture content of about 9% or about 12%, such as harvestedcannabis that has not undergone a drying process) may be provided.Optionally, the botanical material may be comminuted prior to beingintroduced into the extraction chamber in order to increase the surfacearea of the botanical material.

Optionally, the botanical feedstock may be introduced to the extractionchamber in a frozen or partially-frozen state. It will be appreciatedthat any extraction process and any extraction equipment may be used.

At 610, the extraction chamber is operated using a first solvent under afirst set of process conditions to preferentially extract a firstcompound or compounds from the feedstock. For example, a condensable gassolvent (e.g. carbon dioxide) may be introduced into the extractionchamber, and a first set of process conditions within the extractionchamber (pressure, temperature, etc.)

may be controlled so that the botanical material is exposed to firstsolvent at a predetermined state (phase, density, temperature, pressure,etc.) for a predetermined time, during which a first compound present inthe feedstock is preferentially dissolved by the solvent and drawn fromthe botanical feedstock.

For example, where the botanical feedstock includes cannabis, compoundstargeted for selective extraction may include one or more aliphaticaldehydes, one or more terpenes, and one or more cannabinoids.

For example, to preferentially extract a lower molecular weight class ofcompounds using CO₂ solvent, the first set of process conditions mayoperate in the supercritical region of the solvent (e.g. a temperatureof about 40° C., and a pressure of about 1200 psi), resulting in a CO₂density that favors low weight compounds.

The first compound or compounds preferentially extracted at 610 may becharacterized as a ‘target’ or ‘selected’ compound(s) of a first‘targeted’ or ‘selective’ extraction. It will be appreciated that, whilethe first solvent/set of process conditions are selected so as topreferentially extract the first ‘target’ compound, one or moreadditional compounds may nonetheless be extracted from the feedstockduring the first selective extraction.

At 615, first solvent containing the first extracted compound isconveyed from the extraction chamber to the first cyclonic separationstage. For example, first solvent may be withdrawn from extractionchamber 100 and directed along conduit 32, valve 80, and conduit 34 tofirst cyclonic separator 200A.

At 620, some, or preferably most, or more preferably substantially allof the first targeted compound(s) is separated from the first solvent inthe first cyclonic separation stage. For example, the first solvent maybe directed into a cyclone chamber 205A of the first cyclonic separator,and the first compound may be separated from the first solvent andcollected via outlet 230A.

Optionally, at 625, first solvent exiting the first cyclonic separationstage may be recycled to the extraction chamber as discussed previously.For example, first solvent exiting cyclonic separator 200A may bedirected through conduits 42 and 40 and re-introduced to extractionchamber 100.

At 630, the extraction chamber is operated using a second solvent undera second set of process conditions to preferentially extract a secondcompound or compounds from the feedstock. The second solvent may be thesame as the first solvent, or a different solvent may be used.

For example, to preferentially extract a higher molecular weight classof compounds using CO₂ solvent, the second set of process conditions mayalso operate in the supercritical region of the solvent, but at a higherpressure (e.g. a temperature of about 40° C., and a pressure of about3,500 psi), resulting in a CO₂ density that approaches that of theliquid state of CO₂ and favours higher weight compounds. Thus, highermolecular weight compounds can be effectively solvated and extracted.

Alternative solvents to CO₂ can be utilized to favor the extraction ofcomponent that are more hydrophilic. For example, using nitrous oxide asa solvent (either on its own or as a co-solvent with CO₂) the dipolarnature of the nitrous oxide generates a bias to compounds exhibitingdipolar-like regions on their chemical structure. Alternatively, if onewants to select for highly hydrophobic compounds, condensablehydrocarbons (e.g., propane, ethane) may be used as a solvent, to avoidthe extraction of compounds displaying hydrogen bonding or onescontaining areas of large charge distribution.

The second compound or compounds preferentially extracted at 630 may becharacterized as a ‘target’ or ‘selected’ compound(s) of a second‘targeted’ or ‘selective’ extraction. It will be appreciated that, whilethe second solvent/set of process conditions are selected so as topreferentially extract the second ‘target’ compound, one or moreadditional compounds may nonetheless be extracted from the feedstockduring the second selective extraction.

At 635, second solvent containing the second extracted compound isconveyed from the extraction chamber to the second cyclonic separationstage. For example, second solvent may be withdrawn from extractionchamber 100 and directed along conduit 32, valve 80, and conduit 36 tosecond cyclonic separator 2006.

At 640, some, or preferably most, or more preferably substantially allof the second targeted compound(s) is separated from the second solventin the second cyclonic separation stage. For example, the second solventmay be directed into a cyclone chamber 205B of the second cyclonicseparator 200B, and the second compound may be separated from the secondsolvent and collected via outlet 230B.

Optionally, at 645, second solvent exiting the second cyclonicseparation stage may be recycled as discussed previously to theextraction chamber. For example, second solvent exiting cyclonicseparator 200B may be directed through conduits 44, 42, and 40 andre-introduced to extraction chamber 100.

It will be appreciated that, as discussed previously, a plurality ofcyclone stages may be provided in series, wherein each cyclone stage maycomprise one or more cyclone separators operating in parallel and eachstage is designed to remove sequentially lighter extracted compounds.

Preferentially extracting different compounds from the feedstock duringtwo or more selective extractions and separations may have one or moreadvantages. For example, this may provide the ability to fractionategroups of extracted components (e.g. waxes, heavy oils, and light oils)from a single feedstock of botanical material (e.g. cannabis), withouthaving to load/unload the extraction chamber (e.g. during a single‘extraction cycle’).

Additionally, the cyclonic separation stages may each be configured or‘tuned’ to preferentially separate certain selected/targeted compound(s)from solvent. This may allow solvent containing targeted compound(s) tobe directed from the extraction chamber to a cyclonic separator bestsuited to disassociate those compound(s) from solvent. The selectiveextraction and separation of a greater number of compound(s) maysimplify subsequent downstream separations and/or purifications toobtain pure compound isolates.

As used herein, the wording “and/or” is intended to represent aninclusive—or. That is, “X and/or Y” is intended to mean X or Y or both,for example. As a further example, “X, Y, and/or Z” is intended to meanX or Y or Z or any combination thereof.

While the above description describes features of example embodiments,it will be appreciated that some features and/or functions of thedescribed embodiments are susceptible to modification without departingfrom the spirit and principles of operation of the describedembodiments. For example, the various characteristics which aredescribed by means of the represented embodiments or examples may beselectively combined with each other. Accordingly, what has beendescribed above is intended to be illustrative of the claimed conceptand non-limiting. It will be understood by persons skilled in the artthat other variants and modifications may be made without departing fromthe scope of the invention as defined in the claims appended hereto. Thescope of the claims should not be limited by the preferred embodimentsand examples, but should be given the broadest interpretation consistentwith the description as a whole.

1. Apparatus for the extraction of compounds from botanical material,the apparatus comprising: (a) an extraction chamber; (b) a firstcyclonic separation stage comprising at least one first stage cyclonicseparator wherein the at least one first stage cyclonic separator isconfigured to remove a first series of extracted compounds having afirst average molecular weight from a first solvent stream obtained fromthe extraction chamber; (c) a first solvent flow path extending from theextraction chamber to the first cyclonic separation stage; (d) a secondcyclonic separation stage comprising at least one second stage cyclonicseparator wherein the at least one second stage cyclonic separator isconfigured to remove a second series of extracted compounds from asecond solvent stream obtained from the extraction chamber wherein thesecond series of extracted compounds has a second average molecularweight that is higher than the first average molecular weight; (e) asecond solvent flow path extending from the extraction chamber to thesecond cyclonic separation stage; and, (f) at least one valve operableto selectively direct solvent exiting the extraction chamber to one ofthe first cyclonic separation stage and the second cyclonic separationstage.
 2. The apparatus of claim 1, further comprising: a third cyclonicseparation stage comprising at least one third stage cyclonic separatorwherein the at least one third cyclonic stage separator is configured toremove a third series of extracted compounds from a solvent streamwherein the third series of extracted compounds has a third averagemolecular weight that is higher than the second average molecularweight; and, a third solvent flow path extending from the extractionchamber to the third cyclonic separation stage, wherein the at least onevalve is operable to selectively direct solvent exiting the extractionchamber to one of the first cyclonic separation stage, the secondcyclonic separation stage, and the third cyclonic separation stage. 3.The apparatus of claim 1, wherein solvent obtained from the extractionchamber rotates at a first speed in the at least one first stagecyclonic separator and solvent obtained from the extraction chamberrotates at a second speed in the at least one second stage cyclonicseparator wherein the second speed is different than the first speed. 4.The apparatus of claim 2, wherein solvent obtained from the extractionchamber rotates at a first speed in the at least one first stagecyclonic separator, solvent obtained from the extraction chamber rotatesat a second speed in the at least one second stage cyclonic separatorwherein the second speed is different than the first speed, and solventobtained from the extraction chamber rotates at a third speed in the atleast one third cyclonic separator wherein the third speed is differentthan the first speed and the second speed.
 5. The apparatus of claim 1,wherein the first solvent flow path comprises a common solvent flow pathportion downstream of the extraction chamber and upstream of the atleast one valve and a first segregated solvent flow path portiondownstream of the at least one valve and upstream of the first cyclonicseparation stage, and wherein the second solvent flow path comprises thecommon solvent flow path portion and a second segregated solvent flowpath portion downstream of the at least one valve and upstream of thesecond cyclonic separation stage.
 6. The apparatus of claim 2, whereinthe first solvent flow path comprises a common solvent flow path portiondownstream of the extraction chamber and upstream of the at least onevalve and a first segregated solvent flow path portion downstream of theat least one valve and upstream of the first cyclonic separation stage,and wherein the second solvent flow path comprises the common solventflow path portion and a second segregated solvent flow path portiondownstream of the at least one valve and upstream of the second cyclonicseparation stage, and wherein the third solvent flow path comprises thecommon solvent flow path portion and a third segregated solvent flowpath portion downstream of the at least one valve and upstream of thethird cyclonic separation stage.
 7. The apparatus of claim 1, furthercomprising an extraction control system for regulating at least one of atemperature and a pressure of solvent in the extraction chamber, theextraction control system configured to operate the extraction chamberunder at least a first set of process conditions and a second set ofprocess of conditions, and wherein, while the extraction chamber isbeing operated under the first set of process conditions, the at leastone valve is configured to direct solvent exiting the extraction chamberto the first cyclonic separation stage, and wherein, while theextraction chamber is being operated under the second set of processconditions, the at least one valve is configured to direct solventexiting the extraction chamber to the second cyclonic separation stage.8. The apparatus of claim 1, wherein the first average molecular weightis lighter than the second average molecular weight and solvent obtainedfrom the extraction chamber rotates at a first speed in the at least onefirst stage cyclonic separator and solvent obtained from the extractionchamber rotates at a second higher speed in the at least one secondstage cyclonic separator.
 9. A method for extracting compounds frombotanical material using apparatus comprising an extraction chamber, afirst cyclonic separation stage comprising at least one first stagecyclonic separator, and a second cyclonic separation stage comprising atleast one second stage cyclonic separator, the method comprising: (a)introducing a feedstock of botanical material into the extractionchamber; (b) operating the extraction chamber using a first solventunder a first set of process conditions to preferentially extract afirst compound from the feedstock; (c) conveying the first solventcontaining the first extracted compound from the extraction chamber tothe first cyclonic separation stage along a first solvent flow path; (d)separating the first extracted compound from the first solvent in thefirst cyclonic separation stage; (e) operating the extraction chamberusing a second solvent under a second set of process conditions topreferentially extract a second compound from the feedstock; (f)conveying the second solvent containing the second extracted compoundfrom the extraction chamber to the second cyclonic separation stagealong a second solvent flow path; and, (g) separating the secondextracted compound from the second solvent in the second cyclonicseparation stage.
 10. The method of claim 9, further comprisingrecycling the first solvent from the first cyclonic separation stage tothe extraction chamber.
 11. The method of claim 10, further comprisingrecycling the second solvent from the first cyclonic separation stage tothe extraction chamber.
 12. The method of claim 11, wherein the secondsolvent is selected to be the same as the first solvent.
 13. Anapparatus for the extraction of compounds from botanical material, theapparatus comprising: (a) an extraction chamber; (b) a first cyclonicseparation stage comprising at least one first stage cyclonic separatorwherein the at least one first stage cyclonic separator is configured toremove a first series of extracted compounds having a first averagemolecular weight from a solvent stream obtained from the extractionchamber; (c) a first solvent flow path extending from the extractionchamber to the first cyclonic separation stage; (d) a second cyclonicseparation stage comprising at least one second stage cyclonic separatorwherein the at least one second stage cyclonic separator is configuredto remove a second series of extracted compounds from a solvent streamobtained from the first cyclonic separation stage wherein the secondseries of extracted compounds has a second average molecular weight thatis lower than the first average molecular weight; and, (e) a secondsolvent flow path extending from the first cyclonic separation stage tothe second cyclonic separation stage.
 14. The apparatus of claim 13,further comprising: a third cyclonic separation stage comprising atleast one third stage cyclonic separator wherein the at least one thirdcyclonic stage separator is configured to remove a third series ofextracted compounds from a solvent stream wherein the third series ofextracted compounds has a third average molecular weight that is lighterthan the second average molecular weight; and, a third solvent flow pathextending from the second cyclonic separation stage to the thirdcyclonic separation stage.
 15. The apparatus of claim 13, whereinsolvent obtained from the extraction chamber rotates at a first speed inthe at least one first stage cyclonic separator and solvent obtainedfrom the extraction chamber rotates at a second speed in the at leastone second stage cyclonic separator wherein the second speed is higherthan the first speed.
 16. The apparatus of claim 14, wherein solventobtained from the extraction chamber rotates at a first speed in the atleast one first stage cyclonic separator, solvent obtained from theextraction chamber rotates at a second speed in the at least one secondstage cyclonic separator wherein the second speed is higher than thefirst speed, and solvent obtained from the extraction chamber rotates ata third speed in the at least one third cyclonic separator wherein thethird speed is higher than the second speed.
 17. A method for extractingcompounds from botanical material using apparatus comprising anextraction chamber, a first cyclonic separation stage comprising atleast one first stage cyclonic separator, and a second cyclonicseparation stage comprising at least one second stage cyclonicseparator, the method comprising: (a) introducing a feedstock ofbotanical material into the extraction chamber; (b) conducting a firstextraction operation in which the extraction chamber is operated using asolvent under a first set of process conditions to preferentiallyextract a first compound from the feedstock; (c) subsequently conductinga second extraction operation in which the extraction chamber isoperated using the solvent under a second set of process conditions topreferentially extract a second compound from the feedstock wherein thesecond compound has a higher molecular weight than the first compound;(d) conveying the solvent from each extraction operation to the firstcyclonic separation stage and separating the first extracted compoundfrom the solvent in the first cyclonic separation stage; and, (e)conveying partially treated solvent obtained from the first cyclonicseparation stage to the second cyclonic separation stage and separatingthe second extracted compound from the partially treated solvent in thesecond cyclonic separation stage.
 18. The method of claim 17, furthercomprising obtaining fully extracted solvent from the second cyclonicseparation stage and recycling the fully extracted solvent to theextraction chamber.
 19. The method of claim 1, wherein the solventobtained from the extraction chamber rotates at a first speed in the atleast one first stage cyclonic separator and the partially extractedsolvent rotates at a second speed in the at least one second stagecyclonic separator wherein the second speed is higher than the firstspeed.